// 头部
header {
    width: 100%;
    height: 2.75rem;
    text-align: center;
    color: #101010;
    font-size: 1.125rem;
    line-height: 2.75rem;
}


/* 定义动画 */
@keyframes topToBottom {
    0% {
        bottom: 8.75rem;
        font-size: 0;
        opacity: 0;
    }

    40% {
        bottom: 11.25rem;
        font-size: .875rem;
        opacity: 0.5;
    }

    70% {
        bottom: 5rem;
        font-size: 1.5rem;
        opacity: 1;
    }

    100% {
        bottom: 6.25rem;
        font-size: 3rem;
        opacity: 1;
    }
}

// 主体内容
main {
    background: url(../../assets/imgs/advertisement-bg.jpg) no-repeat center/cover;
    position: relative;
    height: 100%;
    width: 100%;
    h1 {
        width: 100%;
        height: 4rem;
        position: absolute;
        bottom: 6.25rem;
        left: 0rem;
        text-align: center;
        font-size: 3rem;
        color: #fff;

        /* 执行动画 */
        animation: topToBottom 1.5s linear;
    }
    div {
        width: 6.5625rem;
        height: 2.5rem;
        background: #fff;
        line-height: 2.5rem;
        text-align: center;
        border: .0625rem solid #bbb;
        border-radius: 1.25rem;
        display: flex;
        justify-content: space-around;
        position: absolute;
        top: 1.75rem;
        right: .875rem;
        font-size: .875rem;
    }
}